JP2001111174A - Substrate for semiconductor device and method of fabrication thereof and semiconductor device using that substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fabricate a flat substrate for a semiconductor device in which defects are suppressed through a simple process. SOLUTION: A GaN buffer layer 12 and a GaN layer 13 are grown on a sapphire substrate 11 at 1050 deg.C and a line and space pattern is formed using lithography and dry etching and then a GaN layer 16 is grown selectively. Subsequently, a line part obtained by removing the buffer layer 12 and the GaN layer 13 and the upper part thereof are removed at a width of 7 μm using lithography and dry etching and a GaN layer 20 is grown selectively thereon. Furthermore, a line part of the GaN layer 16 and the upper part thereof are removed at a width of 7 μm using lithography and dry etching and a GaN layer 23 is grown selectively thereon thus forming a substrate having a low dislocation density over the entire surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for a semiconductor device, a method for manufacturing the same, and a semiconductor device using the substrate for a semiconductor device. TECHNICAL FIELD The present invention relates to a substrate for use, a method for manufacturing the same, and a semiconductor device and a semiconductor laser device using the semiconductor device substrate.

[0002]

2. Description of the Related Art As a short-wavelength semiconductor laser in the 410 nm band, Jpn. Appl. Phys. Lett., Vol.
At 0, after forming GaN on the sapphire substrate,
After forming GaN using selective growth using SiO ₂ as a mask, an n-GaN buffer layer, an n-InGaN crack prevention layer, an AlGaN / n-GaN modulation-doped superlattice are formed on the GaN substrate from which the sapphire substrate has been removed. Cladding layer, n-GaN optical waveguide layer, undoped InGaN / n
-InGaN multiple quantum well active layer, p-AlGaN carrier blocking layer, p-GaN optical waveguide layer, AlGaN / p
A semiconductor laser comprising a -GaN modulation-doped superlattice cladding layer and a p-GaN contact layer has been reported. However, this semiconductor laser still has a high defect density, and reliability at high output has not been obtained.

Also, Ext. Abstr. (MRS Fall Meet. Boston,
1998) G3.38, Pendeo-Epit by TSZheleva
axy-A New Approach For Lateral Growth of Gallium is introduced. Here, without using SiO ₂ as a mask,
After GaN is formed, GaN is stripped off to the sapphire substrate, and GaN is grown on the substrate, and a flat film is formed using the lateral growth of GaN. Have been. Also, using the above method, SPIE Vol.3628 published in 1999,
Although it has been reported that an InGaN multiple quantum well semiconductor laser can be formed, the reliability is limited to a level of 5 mW, and the defect density needs to be further reduced.

In Japanese Patent Application Laid-Open No. 10-312971, Ga
As a method of suppressing cracks caused by the difference in thermal expansion and lattice constant between the N compound semiconductor layer and the sapphire substrate crystal and suppressing the introduction of defects, a growth region is limited by a mask, and a facet structure of a GaN compound semiconductor film is formed by epitaxial growth. Then, a crystal growth method has been reported in which a facet structure is completely buried until the mask is covered, and finally a flat surface is obtained. In this method, since the entire base of the seed growth region is grown on a substrate having a large lattice mismatch, the crystal orientation growing in the lateral direction changes due to the influence of the substrate, and planarization is difficult. However, even if this method is repeated, a difference occurs in the plane orientation, so that the defect cannot be reduced to a practical level.

[0005]

As described above, in a short-wavelength semiconductor laser device, since there are many crystal defects in the substrate, it is difficult to increase the output, and there is a problem in reliability.

In view of the above circumstances, the present invention provides a semiconductor device substrate having a low defect density, a method for manufacturing the same, and a semiconductor device substrate for obtaining a semiconductor device having high reliability even under high output oscillation. It is an object of the present invention to provide a semiconductor element and a semiconductor laser device that have been used.

[0007]

According to a method of manufacturing a substrate for a semiconductor device of the present invention, a first group III nitrogen compound is formed on a base substrate via a buffer layer of AlN or GaN formed by a low-temperature growth method. A first step of forming a layer;
The crystal layer composed of the buffer layer and the first group III nitrogen compound layer is removed in a stripe form up to the base substrate, and a line portion in which the crystal layer is left in a line shape and a space formed between the line portions A line-and-space pattern consisting of a group III part and a second group III nitrogen compound layer thereon, and the line part of the crystal layer as a growth nucleus of a group III nitrogen compound crystal. A second step of forming until the pattern disappears, and removing the line part of the crystal layer and the second group III nitrogen compound layer on the line part at least with the line width until the base substrate is exposed. Thus, a line and space pattern consisting of a line portion in which the second group III nitrogen compound layer is left in a line and a space portion formed between the line portions is formed. The third group III nitrogen compound layer is formed until the line and space pattern of the second group III nitrogen compound layer disappears by using the line part of the second group III nitrogen compound as a growth nucleus of the crystal of the group III nitrogen compound. And a third step.

After the third step, the line part of the line-and-space pattern formed in the immediately preceding step and the group III nitrogen compound layer on the line part are formed at least by the width of the line part. Removed until the base substrate is exposed, to form a line-and-space pattern consisting of a line portion where the group III nitrogen compound layer is left in a line and a space portion formed between the line portions, Above, the step of forming a group III nitrogen compound layer until the line and space pattern disappears may be performed at least once using the line portion as a growth nucleus of a crystal of the group III nitrogen compound.

Another method of manufacturing a substrate for a semiconductor device according to the present invention is directed to a method for manufacturing an Al substrate formed on a base substrate by a low-temperature growth method.
Forming a buffer layer made of N or GaN, forming a first group III nitrogen compound layer thereon, and forming a crystal layer consisting of the buffer layer and the first group III nitrogen compound layer in a stripe shape. To the base substrate to form a line-and-space pattern comprising a line portion in which the crystal layer is left in a line shape and a space portion formed between the line portions, and a second pattern is formed thereon. A second step of forming a group III nitrogen compound layer until the line and space pattern disappears, using the line part of the crystal layer as a growth nucleus of the crystal of the group III nitrogen compound, and the line part of the crystal layer and the line part of the line part. The upper second group III nitrogen compound layer is removed in a V-groove shape or an inverted trapezoidal shape until a part of the base substrate is exposed, and the second group III nitrogen compound layer is left in a line shape. Line section and the line section A pattern of lines and spaces comprising the formed space portion is formed, thereon a third Group III nitride layer, the second III
Forming a line portion of the group III nitrogen compound layer as a growth nucleus of a crystal of the group III nitrogen compound, and forming a line and space pattern of the second group III nitrogen compound layer until the pattern disappears. Things.

[0010] The group III nitrogen compound layer may be formed while doping impurities.

[0011] After the last of the above steps, the base substrate may be removed.

The base substrate is made of sapphire, SiC,
ZnO, LiCaO ₂ , LiAlO ₂ , GaAs, ZnS
Desirably, it is any one selected from the group consisting of e, GaP, Ge and Si.

The buffer layer and the group III nitrogen compound layer are preferably formed by HVPE, MOCVD or MBE.

The group III nitrogen compound layer is made of GaN, In,
Desirably, it is made of one selected from the group consisting of GaN, AlGaN, InAlGaN, InAlN, and InN.

A semiconductor device substrate according to the present invention is manufactured by the method for manufacturing a semiconductor device substrate described above.

A semiconductor element according to the present invention is characterized in that a semiconductor layer is provided on a semiconductor element substrate manufactured by the method for manufacturing a semiconductor element substrate described above.

The semiconductor laser device of the present invention comprises a semiconductor layer on a semiconductor element substrate manufactured by the above-described method for manufacturing a semiconductor element substrate, and serves as a current injection window formed in the semiconductor layer. The stripe width is 10 μm or more.

[0018]

According to the method of manufacturing a semiconductor device substrate of the present invention, a line-and-space pattern is formed after a group III nitrogen compound is grown on a base substrate via a buffer layer. A group III nitrogen compound is crystal-grown, and a line-and-space pattern is formed again to remove the portion left in the previous line, that is, the portion where the dislocation has occurred in the layer above the buffer layer. To
Since the crystal of the group III nitrogen compound is grown, a substrate of the group III nitrogen compound having a small number of dislocations can be easily obtained without going through a complicated process. Further, since there is almost no dislocation, high output can be achieved and reliability can be improved.

Further, by repeating the above-mentioned step, that is, the step of selectively growing after removing the dislocation-producing portion in the form of a stripe, a substrate having no dislocation can be obtained completely.

According to another method of manufacturing a substrate for a semiconductor device of the present invention, a semiconductor substrate is provided on a base substrate via a buffer layer.
After growing the group I nitrogen compound, the buffer layer and the group III nitrogen compound layer are removed in a V-groove or inverted trapezoidal shape to form a line-and-space pattern, on which the group III nitrogen compound is grown. Therefore, a substrate with few dislocations can be obtained as described above. In addition, by removing in a V-groove shape or an inverted trapezoid shape, a portion where the base substrate and the buffer layer grown at a low temperature are in contact is left.
There is an advantage that the layer of the group III nitrogen compound on the base substrate is difficult to peel off.

Further, a conductive substrate can be manufactured by doping impurities when growing a group III nitrogen compound crystal.

Further, by removing the base substrate at the end of the process, electrical conduction can be obtained from the back surface of the substrate.

A semiconductor element, for example, a semiconductor light emitting element, a field effect transistor, a semiconductor laser device,
It is possible to manufacture a semiconductor optical amplifier or a photodetector.

In particular, by using a semiconductor element substrate manufactured as described above for a semiconductor laser device having a stripe width of 10 μm or more, a highly reliable laser can be obtained even with a high output.

Therefore, the semiconductor device as described above can be used in the fields of high-speed information / image processing, communication, measurement, medical treatment, and printing.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings.

A method of manufacturing a semiconductor device substrate according to the first embodiment of the present invention will be described. FIG. 1 shows a process of manufacturing the semiconductor device substrate.

As shown in FIG. 1A, trimethylgallium (TMG) and ammonia are used as a raw material for growth, silane gas is used as an n-type dopant gas, and cyclopentadienyl magnesium is used as a p-type dopant. Using (Cp ₂ Mg), a GaN buffer layer 12 having a thickness of about 20 nm is formed on a (0001) C-plane sapphire substrate 11 at a temperature of 500 ° C. Subsequently, the temperature is set to 1050 ° C., and the GaN layer 13 is grown to about 2 μm.
After that, an SiO ₂ layer 14 is formed, a resist 15 is applied, and then, using normal lithography,

[0029]

(Equation 1)

The SiO ₂ film 14 having a width of 5 μm is removed in the direction, and a line composed of a line portion where the GaN layer is left in a line shape and a space portion formed between the line portions is formed at a period of about 10 μm. An and space (hereinafter, referred to as a line and space) pattern is formed. Using the resist 15 and the SiO ₂ film 14 as a mask, the buffer layer 12 and the GaN layer 13 are removed to the upper surface of the sapphire substrate 11 by dry etching using a chlorine-based gas.

Next, as shown in FIG.
After removing the iO ₂ film 14, the GaN layer 16 is selectively grown to about 20 μm. At this time, the space portion is finally filled by the lateral growth, and the surface is flattened. Buffer layer 12
Since the GaN layer 13 and the GaN layer 13 originally have many dislocations, threading dislocations 17 are generated at the upper part of the line portion at this time.

[0032] Next, as shown in FIG. 1c, SiO ₂ film 18
Is formed, and a resist 19 is applied. Then, using a normal lithography, a 7 μm width is formed at a substantially central position of a line portion of the buffer layer 12 and the GaN layer 13.

[0033]

(Equation 1)

The SiO ₂ film 18 is removed in the direction
A line-and-space pattern is formed at about a period. Therefore, the line width of the SiO ₂ film 18 and the resist 19 is 3
It is about μm.

Next, as shown in FIG. 1D, using the resist 19 and the SiO ₂ film 18 as a mask, a chlorine-based gas is used to form a line portion of the buffer layer 12 and the GaN layer 13 and a G portion on the line portion.
The aN layer 16 is dry-etched to form a sapphire substrate 11.
Remove to the top. As a result, portions of the GaN layer 16 where the dislocation density is large are removed. After that, the SiO ₂ film 18 and the resist film 19 are removed.

Next, as shown in FIG. 1E, a GaN layer 20 is selectively grown to a thickness of about 20 μm. At this time, the space portion is finally filled by the lateral growth, and the surface is flattened. As a result, a region having a low dislocation density is formed over the entire surface.

Next, as shown in FIG. 1f, SiO ₂ film 21
Is formed, and a resist 22 is applied. Then, using a normal lithography, a 7 μm width is formed at a substantially central position of the line portion of the GaN layer 16.

[0038]

(Equation 1)

The SiO ₂ film 21 is removed in the direction
A line-and-space pattern is formed at about a period. Therefore, the line width of the SiO ₂ film 21 and the resist 22 is 3
It is about μm.

Thereafter, as shown in FIG. 1g, using the resist 22 and the SiO ₂ film 21 shown in FIG. 1f as a mask, the line portion of the GaN layer 16 and the GaN layer 20 thereabove are formed using a chlorine-based gas. It is removed to the upper surface of the sapphire substrate by dry etching. After removing the resist 22 and the SiO ₂ film 21, a GaN layer 23 is selectively grown to about 20 μm. At this time,
Lateral growth eventually fills the space and planarizes the surface. As a result, a substrate having a low dislocation density can be obtained over the entire surface.

Further, by repeating the above-described steps of etching the GaN layer and selectively growing, the dislocation density can be reduced.

A GaN-based semiconductor layer such as GaN, InGaN, AlGaN, InG
A semiconductor light emitting element and an electronic device can be manufactured by crystal growth of aAlN or the like.

On the GaN substrate manufactured as described above, a GaN layer is further grown to a thickness of about 100 to 200 μm, and the sapphire substrate is peeled off.
By growing crystals of N, InGaN, AlGaN, InGaAlN, or the like, a semiconductor light emitting element and an electronic device can be manufactured.

In the present embodiment, the case of undoping without doping impurities when the GaN layer is selectively grown has been described.
Type GaN conductive substrate can be manufactured. When Mg is doped as a p-type impurity, a heat treatment is performed in a nitrogen atmosphere after growth or a growth is performed in a nitrogen-rich atmosphere to activate Mg. Is also good.

As a growth method, gallium (Ga) is used.
Hydride VPE method using GaCl, which is a reaction product of hydrogen chloride (HCl) with ammonia (NH ₃ ), may be used.

A method of manufacturing a semiconductor device substrate according to a second embodiment of the present invention will be described. FIG. 2 shows a process of manufacturing the semiconductor device substrate.

As shown in FIG. 2A, trimethylgallium (TM) was used as a growth material by metal organic chemical vapor deposition.
G) and ammonia, and as an n-type dopant gas,
Silane gas is used, and cyclopentadienyl magnesium (Cp ₂ Mg) is used as a p-type dopant. (0
001) A at a temperature of 500 ° C. on a 6H-SiC substrate 31
The 1N buffer layer 32 is formed with a thickness of about 20 nm. Subsequently, the temperature is set to 1050 ° C., and the GaN layer 33 is grown to about 2 μm. Thereafter, an SiO ₂ film 34 is formed, and a resist 3
After applying 5, using normal lithography,

[0048]

(Equation 1)

The SiO ₂ film 34 having a width of 5 μm is removed in the direction, and a line and space pattern is formed at a period of about 10 μm. Using the resist 35 and the SiO ₂ film 34 as a mask, a GaN layer 33 and an AlN
The buffer layer 32 is dry-etched to form the SiC substrate 31.
Remove to the top.

Next, as shown in FIG. 2B, after removing the resist 35 and the SiO ₂ film 34, a GaN layer 36 is selectively grown to about 20 μm. At this time, the space portion is finally filled and the surface is flattened by the lateral growth. Since the buffer layer 32 and the GaN layer 33 originally have many dislocations, threading dislocations 37 are generated at the upper part of the line portion at this point.

Next, as shown in FIG. 2c, SiO ₂ film 38
Is formed, a resist 39 is applied, and a normal lithography is used to form a 7 μm width at a substantially central position of a line portion between the buffer layer 32 and the GaN layer 33.

[0052]

(Equation 1)

The SiO ₂ film 38 is removed in the direction
A line-and-space pattern is formed at about a period. Therefore, the line width of the SiO ₂ film 38 and the resist 39 is 3
It is about μm.

Next, as shown in FIG. 2D, using the resist 39 and the SiO ₂ film 38 as a mask, the G
The aN layer 36 is removed to the upper surface of the SiC substrate 31 by dry etching, and thereafter, the resist 39 and the SiO ₂ film 38 are removed.

Next, as shown in FIG. 2E, a GaN layer 40 is selectively grown to about 20 μm. At this time, the space portion is finally filled by the lateral growth, and the surface is flattened.

Next, as shown in FIG. 2f, SiO ₂ film 41
Is formed and a resist 42 is applied. Then, using a normal lithography, 7
μm width

[0057]

(Equation 1)

The SiO ₂ film 41 is removed in the direction
A line-and-space pattern is formed at about a period. Therefore, the remaining line width of the SiO ₂ film 41 and the resist 42 is about 3 μm.

Next, as shown in FIG. 2G, using the resist 42 and the SiO ₂ film 41 as a mask, the G
After removing the aN layer 40 to the upper surface of the SiC substrate by dry etching, the GaN layer 43 is selectively grown to about 20 μm. At this time, the space portion is finally filled and the surface is flattened by the lateral growth. As a result, a substrate having a low dislocation density over almost the entire surface can be obtained.

By repeating the steps of etching and selective growth of the GaN layer, a substrate having a lower dislocation density can be obtained.

Also in this embodiment, a GaN-based semiconductor layer, for example, GaN, is formed on the substrate manufactured as described above.
By growing crystals of InGaN, AlGaN, InGaAlN, or the like, a semiconductor light emitting element and an electronic device can be formed.

Alternatively, a GaN layer is grown to a thickness of about 100 to 200 μm on the GaN substrate manufactured as described above, and the SiC substrate is removed by polishing or chemical etching.
GaN-based semiconductor layer, for example, GaN, InGaN, AlG
Semiconductor light emitting elements and electronic devices can also be manufactured by growing crystals of aN, InGaAlN, or the like.

Here, the base substrate is (0001) plane 4H
-A SiC substrate may be used.

In the present embodiment, the case of undoping without doping impurities when selectively growing a GaN layer has been described.
Type GaN conductive substrate can be manufactured. For example,
When Mg is doped as a p-type impurity, either a heat treatment is performed in a nitrogen atmosphere after growth or a growth is performed in a nitrogen-rich atmosphere to activate Mg. It is desirable. By manufacturing a conductive substrate by doping impurities, an electrode can be formed on the substrate side.

The GaN layer may be grown by a hydride VPE method using GaCl, which is a reaction product of gallium (Ga) and hydrogen chloride (HCl), and ammonia (NH ₃ ), or a molecular beam using a gas source. An epitaxial growth method may be used.

Next, a method of manufacturing a semiconductor device substrate according to a third embodiment of the present invention will be described. FIG. 3 shows a process of manufacturing the semiconductor device substrate.

As shown in FIG. 3A, trimethylgallium (TM
G) and ammonia, and as an n-type dopant gas,
Using silane gas and cyclopentadienyl magnesium (Cp ₂ Mg) as a p-type dopant,
01) Ga on a C-plane sapphire substrate 51 at a temperature of 500 ° C.
The N buffer layer 52 is formed with a thickness of about 20 nm. Subsequently, at a temperature of 1050 ° C., a GaN layer 53 is grown to about 2 μm. Thereafter, an SiO ₂ film 54 is formed, and a resist 55
After applying, using normal lithography,

[0068]

(Equation 1)

The SiO ₂ film 54 having a width of 5 μm is removed in the direction, and a line and space pattern is formed at a period of about 10 μm.

Next, as shown in FIG. 3B, the GaN buffer layer 52 and the GaN layer 53 are removed to the upper surface of the sapphire substrate 51 by dry etching. After that, the resist 55 and the SiO ₂ film 54 on the GaN layer 53 are removed.

Next, as shown in FIG. 3C, a GaN layer 56 is selectively grown to about 20 μm. At this time, the space portion is finally filled and the surface is flattened by the lateral growth. Thereafter, an SiO ₂ film 58 is formed, a resist 59 is applied, and the GaN buffer layer 52 is
At the center of the line portion of the GaN layer 53 with a width of 7 μm

[0072]

(Equation 1)

The SiO ₂ film 58 is removed in the direction
A line-and-space pattern is formed at about a period. Therefore, the line width of the SiO ₂ film 58 and the resist 59 is 3
It is about μm.

Next, as shown in FIG. 3D, using the resist 59 and the SiO ₂ film 58 as a mask, the GaN layer 56 is removed in a V-groove shape up to the upper surface of the sapphire substrate 51 by wet etching.

Thereafter, as shown in FIG.
After the removal of the SiO ₂ film 58, the GaN layer 60 is selectively grown to about 20 μm. At this time, due to the lateral growth, the V-groove is finally buried and the surface is flattened. As a result, a substrate having a low dislocation density over the entire surface of the substrate can be obtained.

The shape by wet etching is not limited to the V-groove shape, but may be an inverted trapezoidal shape.

A GaN-based semiconductor layer (GaN, InGaN, AlGaN, InGaAs) is formed on the substrate manufactured as described above.
1N) can be used to produce semiconductor light emitting devices and electronic devices.

Further, in the above three embodiments, the case where the sapphire substrate and the SiC substrate are used as the base substrate has been described, but ZnO, LiGaO ₂ , LiA
10 ₂ , ZnSe, GaAs, GaP, Ge, Si, and the like can also be used, and a substrate for a semiconductor element can be manufactured by the same method as in the above embodiment.

As a mask material, besides SiO ₂ , SiN
A mask material having good heat resistance to high temperatures, such as AlN and TiN, may be used.

In the present embodiment, the method of forming a GaN substrate has been described. However, instead of growing GaN,
By growing GaN, AlGaN, InAlGaN, InAlN, InN, and the like, a substrate other than GaN can be manufactured.

Next, a description will be given of a semiconductor laser device according to a fourth embodiment of the present invention. FIG. 4 is a sectional view of the semiconductor laser device.

According to the first embodiment, GaN is selectively grown on a base substrate, and the base substrate is peeled off to manufacture an n-type GaN substrate 71. As shown in FIG.
On this GaN substrate 71, n-GaN buffer layers 72, 15
0 pairs of n-Al _0.14 Ga _0.86 N (2.5 nm) / GaN
The (2.5 nm) superlattice cladding layer 73 is formed of an n-GaN optical waveguide layer 74 and n-In _0.02 Ga _0.98 N (10.5 nm) / n.
-In _0.15 Ga _0.85 N (3.5 nm) triple quantum well active layer 75, p-Al _0.2 Ga _0.8 N carrier block layer 76, p
-GaN optical waveguide layer 77, 150 pairs of p-Al _0.14 Ga
_{A 0.86} N (2.5 nm) / GaN (2.5 nm) superlattice cladding layer 78 and a p-GaN contact layer 79 are laminated. p
As a method of activating the type of impurity Mg, either a method of performing a heat treatment in a nitrogen atmosphere after the crystal growth or a method of growing the crystal in a nitrogen-rich atmosphere may be used.

Subsequently, an SiO ₂ film 80 (not shown) is formed, and the SiO ₂ film 80 outside the stripe region having a width of 3 μm is removed by ordinary lithography. By selective etching with RIE (Reactive Ion Etching Equipment)
Etching is performed partway through the p-type superlattice cladding layer 78.
The remaining thickness of the cladding layer in this etching is a thickness that can achieve the fundamental transverse mode oscillation. Thereafter, the SiO ₂ film 80 is removed, a SiO ₂ film 81 is subsequently formed, the SiO ₂ film 81 on the stripe is removed, and a p-electrode 82 of Ni / Au is formed. Thereafter, the substrate is polished, an n-electrode 83 made of Ti / Au is formed, and a high-reflection coat and a low-reflection coat are applied to the resonator surface formed by cleaving the sample. Finalize.

The wavelength band λ at which the semiconductor laser device oscillates
As for the active layer, In _x4 Ga _1-x4 N is used as the active layer, and the composition ratio is
By setting 0 ≦ X4 ≦ 0.5, 360 ≦ λ ≦ 550 (n
Control up to the range of m) is possible.

Further, the conductivity of the semiconductor layer may be inverted (n-type and p-type are interchanged).

In this embodiment, a semiconductor laser having a narrow stripe fundamental mode oscillation has been described. However, the present invention relates to a semiconductor laser device having a wide stripe of 10 μm or more, a field effect transistor, a semiconductor laser device, a semiconductor optical amplifier, and a semiconductor laser device. It can also be applied to the manufacture of semiconductor light emitting devices and the like.

[Brief description of the drawings]

FIG. 1 is a view showing a manufacturing process of a semiconductor device substrate according to a first embodiment of the present invention;

FIG. 2 is a view showing a manufacturing process of a semiconductor device substrate according to a second embodiment of the present invention;

FIG. 3 is a view showing a process of manufacturing a semiconductor device substrate according to a third embodiment of the present invention;

FIG. 4 is a sectional view showing a semiconductor laser device according to a fourth embodiment of the present invention;

[Explanation of symbols]

11,51 Sapphire substrate 31 SiC substrate 12,52 GaN buffer layer 32 AlN buffer layer 13,33,53 GaN layer 14,18,34,38,54,58 SiO ₂ film 15,19,35,39,55,59 Resist 16,20,23,36,40,43,56,60 GaN layer 17,37,57 Threading dislocation 71 GaN layer 72 GaN buffer layer 73 n-AlGaN / GaN superlattice cladding layer 74 n-GaN optical waveguide layer 75 n-InGaN / InGaN triple quantum well active layer 76 p-AlGaN carrier blocking layer 77 p-GaN optical waveguide layer 78 p-AlGaN superlattice cladding layer 79 p-GaN contact layer 81 SiO ₂ film 82 p electrode 83 n electrode

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) DA54 DA55 DB04 HA13 HA16 5F073 AA13 AA74 AA77 CA07 CB05 CB07 DA05 DA25 EA24 EA28 5F102 GA19 GB01 GC01 GJ02 GJ03 GJ04 GJ05 GJ09 GJ10 GK04 GR01 HC01 HC15

Claims (11)

[Claims] A first step of forming a first group III nitrogen compound layer on a base substrate via a buffer layer of AlN or GaN formed by a low-temperature growth method; The crystal layer made of one group III nitrogen compound layer is removed in a stripe form up to the base substrate, and the crystal layer is removed from a line portion left in a line shape and a space portion formed between the line portions. To form a line and space pattern, on which the second II
A second step of forming a group I nitrogen compound layer with the line portion of the crystal layer as a growth nucleus of a crystal of the group III nitrogen compound until the line and space pattern disappears, and a line portion of the crystal layer and The second group III nitrogen compound layer above the line portion is removed at least with the line width until the base substrate is exposed, leaving the second group III nitrogen compound layer in a line. A line and space pattern comprising a line portion and a space portion formed between the line portions, and a third group III nitrogen compound layer is formed thereon, and a line of the second group III nitrogen compound is formed. Part is a growth nucleus of a crystal of a group III nitrogen compound,
A third step of forming a line and space pattern of the second group III nitrogen compound layer until the pattern disappears. 2. After the third step, the line part of the line and space pattern formed in the immediately preceding step and the group III nitrogen compound layer on the line part are formed at least in the width of the line part. Removing the base substrate until the base substrate is exposed to form a line and space pattern including a line portion in which the group III nitrogen compound layer is left in a line shape and a space portion formed between the line portions; The method according to claim 1, wherein the step of forming a group III nitrogen compound layer until the line and space pattern disappears is performed at least once using the line portion as a growth nucleus of a crystal of the group III nitrogen compound. 2. The method for manufacturing a substrate for a semiconductor element according to 1. 3. A first step of forming a buffer layer made of AlN or GaN formed on a base substrate by a low-temperature growth method, and forming a first group III nitrogen compound layer thereon, The layer and the crystal layer composed of the first group III nitrogen compound layer are removed in a stripe form up to the base substrate,
The crystal layer forms a line-and-space pattern consisting of a line portion left in a line shape and a space portion formed between the line portions, and a second Group III nitrogen compound layer thereon, A second step of forming the line portion of the crystal layer as a growth nucleus of a crystal of a group III nitrogen compound until the line and space pattern disappears, and the line portion of the crystal layer and the second portion above the line portion. A line portion in which the second group III nitrogen compound layer is removed in a V-groove shape or an inverted trapezoidal shape until a part of the base substrate is exposed, and the second group III nitrogen compound layer is left in a line shape. And a line and space pattern consisting of a space portion formed between the line portions,
The line and space pattern of the second group III nitrogen compound layer is defined as a third group III nitrogen compound layer, and the line portion of the second group III nitrogen compound layer is used as a growth nucleus of a crystal of the group III nitrogen compound. And a third step of forming the substrate until it disappears. 4. The method according to claim 1, wherein the group III nitrogen compound layer is formed while doping impurities.
4. The method for manufacturing a semiconductor element substrate according to 2 or 3. 5. The method according to claim 1, wherein the base substrate is removed after the last of the steps.
5. The method for manufacturing a semiconductor element substrate according to 3 or 4. 6. The base substrate is made of sapphire, Si
C, ZnO, LiCaO ₂ , LiAlO ₂ , GaAs, Z
6. The semiconductor device according to claim 1, which is any one selected from the group consisting of nSe, GaP, Ge, and Si.
A method for manufacturing a substrate for a semiconductor element according to any one of the preceding claims. 7. The substrate for a semiconductor device according to claim 1, wherein said buffer layer and said group III nitrogen compound layer are formed by HVPE, MOCVD or MBE. Manufacturing method. 8. The group III nitrogen compound layer is composed of GaN, I
The method for manufacturing a substrate for a semiconductor device according to claim 1, wherein the method comprises one selected from the group consisting of nGaN, AlGaN, InAlGaN, InAlN, and InN. 9. A substrate for a semiconductor device manufactured by the method for manufacturing a substrate for a semiconductor device according to claim 1. 10. A semiconductor device comprising a semiconductor device substrate manufactured by the method for manufacturing a semiconductor device substrate according to claim 1 and a semiconductor layer provided on the semiconductor device substrate. 11. A semiconductor element substrate provided on a semiconductor element substrate manufactured by the method for manufacturing a semiconductor element substrate according to any one of claims 1 to 8, wherein a semiconductor layer is provided. The width of the stripe serving as the injection window is 10 μm
A semiconductor laser device characterized by the above.